I´m running five accesspoints (RB500) on five different locations. All are connected to a centralized PPPoE Server (via EoiP). Customers are connecting to the accesspoints and "dial in" into the PPPoE Server.

Everything works very fine. But if the pppoe-server reaches about 45 - 50 sessions and a traffic of about 4 - 5 mbit/s (all users together), many sessions get disconnected for 5 to 15 seconds. All wlan-bridge-connections from accesspoints to the pppoe-server are running stable 24 or 36 mbit links.

I examined the cpu and memory utilization of the PPPoE Server, but both is very low. My PPPoE-Server is a 2,4 Celeron with 512 MB RAM. All PPPoE sessions don´t use MPPE.

Did anyone have similar experiences?

Thanks so far.
canram.

what pppoe server do you use - mikrotik ?
whitch version ?

Yes. All used components are Mikrotik and all are running Router OS 2.9.5.

why do you use Eoip ?
what hardware do you use ?

i would prefere Vlans - we do it this way here
with about 50 APs and up to >250 concurrent users on one of the pppoe servers and have no probelems.
all the Vlans terminate on the pppoe server each vlan has one eth - and one pppoe server per eth
about 4000 hours uptime...

why do you use Eoip ?

Because in RouterOS no pppoe-relay exists and I need to transport Ethernet-Packets (pppoe) via a routed network to the centralized pppoe-server.

what hardware do you use ?

All APs and bridges are RB500.
The PPPoE-Server ist a 2,4 GHz Celeron with 512 MB Ram and INTEL-Nics.

i would prefere Vlans - we do it this way here
with about 50 APs and up to >250 concurrent users on one of the pppoe servers and have no probelems.
all the Vlans terminate on the pppoe server each vlan has one eth - and one pppoe server per eth
about 4000 hours uptime...

So your assumption is that my EoIP-Tunnels are causing this problem? The VLAN-solution sounds interessting. So, on each AP you use a seperated own vlan bridged with the public wlan-interfaced and terminating on the pppoe-server which means about 50 vlans on the pppoe-server? You simply use vlan instead of an EoIP-Tunnel? But how transport the packets over a routed and meshed network. I need to configure each vlan on each router?

Unfortunatly PPPoE requires no routing. Have you thought of de-centralizing the PPPoE servers and let the RB500 terminate the PPPoE session then rout it back from there?

I don´t want to act the RB500s as PPPoE-Server because I don´t want to seperate the IP-Pool, the PPPoE-Server gets his clients-IPs from.

By the way, yesterday (sunday) there was also big traffic and many simultaneous sessions on my PPPoE Server and I experienced the same problem. I have several APs with EoIP Tunnels to my PPPoE-Server. On some APs, there´re many clients and on some other, there´re are only 3 or 4 clients.

But, I observed the PPPoE-Disconnects at many clients, independently on which AP they have subscribed. At the same time, 12 PPPoE-sessions from clients via 5 different APs got disconnected and reconnected after 10 seconds. The PPPoE-Server has two "extern"-Interfaces. Two of those APs use extern1 and the other three use extern2.

Therefore, the problem can not depend on the EoIP-Tunnel, a damaged NIC or the AP. It must be a problem of the centralized PPPoE-Server.

But I don´t know, how to fix?